Quote Originally Posted by zanes View Post
Chaps,

Interesting one here. I've always been told and read that when you're reloading cases that have not been fired in the rifle you're reloading for you must neck size. No qualifications, no "but if they chamber OK you're OK neck sizing only".

My question is- what am I missing here; the only reason I can think of for full length sizing is to prevent issues with the brass not fitting in the rifle's chamber (for a bolt action for target shooting). I have a quantity of once fired .300 Win Mag brass for my new to me rifle which was not fired in the rifle.

Happy to full length resize this time if necessary, but prefer neck sizing and trying to work out why I shouldn't.
Its an odd one Zanes.

Some folk I know insist on FL sizing every firing. If you do that with a rifle that has a generous head space, you may well be speeding up the destruction of your brass by work hardening it near the head and stretching and compressing it as the lot moves forwards and stops at the shoulders.

When I used to FL resize for my .303, the brass would give up after about 3 shots. As soon as I went to neck only (after an initial reset for once fired) they last for 10 or so...I have not had a separation since doing this and the primer pockets tend to give up before the cases do.

It depends a lot on your rifle, but with once fired brass I would always normalise it and work from there. I recently had a first which was my M67 refusing to chamber some hand loads. I had (without thinking about it) bunged some fresh brass in to top up some lost cases that had been prepped, less FL sizing.

They had come from a big bag of .308 that had been through any one of 12 AIs, my bad...

I now have 3 big tubs and when cases come back they get dumped into the "Needs cleaning" tub. When de-capped and cleaned they go into the "Needs sizing tub" where they get that and any trimming that needs doing, then they go to the "loading" tub....all in their respective boxes of course.

Also, some rifles actually seem to shoot FL resized cases better for each firing. Some will also become un-chamberable after 5 firings or so (A certain to shot told me that he FL resized after 5 firings after not being able to chamber rounds that had been fired in his rifle but just neck sized).

There is no one size fits all solution mate. My intention is to work the brass and my fingers as little as possible....and keep it consistent.

Oddly, if I use federal .308 brass (which I have been using as they come free) I need to open the necks with a mandrel after any sizing as they tend to scrape the bullets.